GB2126973A

GB2126973A - Conveyor belt curve

Info

Publication number: GB2126973A
Application number: GB08321014A
Authority: GB
Inventors: Hans Widmer
Original assignee: BUEHRER TRANSVER AG; Transver AG
Current assignee: BUEHRER TRANSVER AG; Transver AG
Priority date: 1982-09-03
Filing date: 1983-08-04
Publication date: 1984-04-04
Also published as: FR2532630B3; DE3326688C2; CH657827A5; FR2532630A3; GB2126973B; GB8321014D0; NL189957B; IT1159591B; NL189957C; DE3326688A1; NL8302846A; IT8367894A0; US4846338A

Description

1 GB 2 126 973 A 1

SPECIFICATION Conveyor belt curve

The present invention concerns a conveyor belt curve.

It is known that in some conveyor belt installations the goods to be conveyed have to be moved along curves and other parts comprising rounded portions, either because, for reasons of space, a processing line has to be arranged in a zig-zag manner, or because the difference in level has to be overcome by moving the material upwards along a spiral conveyor path.

CH-A 599 890 discloses an endless circular belt which is tensioned by means of two rows of roller, the axes of which form an angle of 901. 80 Disposed at the outer periphery is a driven conveyor chain, which is guided in a rail arrangement for determining the curvature. Over its entire outer periphery the conveyor belt is secured to the conveyor chain by means of spaced drive members, such as for example, spiral tension springs. The conveyor chain can be guided in the rail by means of a channeled block, or the conveyor chain can itself be accommodated in a channelled guide rail and it may consist of rollers.

With these conveyor belt installations, there arises the problem of replacing dirty of damaged belts. Because of the tapered form of the entire installation, the belt that is to be replaced must either be cutup into pieces or withdrawn towards the centre of the curve. If the conveyor belt can be removed only by being cut up, the replacement belt has to be inserted in the flattened out condition and joined In situ to form an endless belt. It will be readily appreciated that, if this procedure is used, the belt tension can vary within wide lines so that the lower run sags and this can lead to operating troubles in the case of spiral conveyors when the unoccupied space has a vertical dimension for permitting unrestricted passage of the material.

Constant tension can be achieved only if the belts have closed manufacturing tolerances. Thus, the conveyor belts have to be extracted towards the centre point of the curve and from that point they must be reinserted. With large widths of conveyor belts and in the case of large radii, extraction towards the centre can become a complicated matter, particularly when the space within the curve is used for accommodating 115 columns or other objects. However, the replacement of conveyor belts can become difficult even when no impeding objects are present; thus, difficulty arises when a guide, located at the inside of the curve and comprising a 120 second chain, is provided, or even when the frame at the inside of the curve and serving to mount the rows of rollers and for holding rubbing plates or the like, has to be removed and the installations arranged overhead.

The object of the present invention is, therefore, to provide a solution to the problem of installing and removing the conveyor belts in systems comprising belt curves.

According to the invention, this object is achieved by means of a conveyor belt curve comprising an endless conveyor belt which is mounted between two rows of rollers supported on shafts which are secured on an outer frame and an inner frame and form an angle at least in one projection, resilient drive members securing the conveyor belt at its convex longer face to a conveyor chain, said conveyor chain being guided in guide rails defining the curvature, wherein the shaft of at least one of the two rows of rollers is secured in a dire ction-cha n gi ng head which is mounted to be swung out from the face of the upper run of the conveyor belt, and means are provided between the outer frame and the inner frame forming at least one slot for the introduction and removal of the conveyor belt.

Some embodiments of the invention will now be described by way of example, reference being made to the accompanying drawings, in which:

Figure 1 is a plan view of a 901 conveyor belt curve, part of the belt shown as being broken off, Figure 2 is, on a larger scale, a sectional view along the line 11-11 of Figure 1, Figure 3 is a plan view of part of the conveyor belt with a resilient drive member, Figure 4 is a side view of a direction-changing head as seen in the direction of the arrow IV in Figure 1, Figure 5 is a plan view of a portion of a curve with a first type of support for the conveyor belt, Figure 6 is a sectional view along the line VI-VI of Figure 5, Figure 7 is a plan view of part of a curve with a second type of support for the conveyor belt, Figure 8 is a sectional view along the line Vill-VIII of Figure 7, and Figure 9 is a perspective view of the stand of a conveyor belt curve with a third type of support for the conveyor belt.

Referring to Figures 1 to 3 of the drawings, the 901 conveyor belt curve shown comprises a known endless belt, the upper run 1 a of which has curved edges 4 and 5. The conveyor belt 1 develops along a semicircle. The conveyor belt 1 passes round two rows of cylindrical rollers 6 and 7, the shafts 9 and 10 are at an angle of 900. The rollers 6 and 7 are mounted to rotate freely on the said shafts 9 and 10. The edge 4 of the belt at the outside of the curve lies on a flat support face 11 which is part of an annular member 12 which carries two guide rails 13 and 14 with openings for the two runs of an endless conveyor chain 16 for driving the conveyor belt 1. The conveyor chain is driven by a motor, not illustrated. The conveyor chain 16 carries equidistantly spaced angled support straps 17 to which is rigidly attached a bearing pin 18 for a roller 19. The bearing pin 18 has a head 20 with a peripheral channel 21 for holding a resilient drive member 22. Rings made of an elastomer are advantageously used as the drive members 22.

As they rotate, the rollers 19 are supported by their cylindrical faces on a guide surface 23 of the guide rails 13 and 14. In this arrangement, the 2 GB 2 126 973 A 2 drive members 22 are secured to the conveyor belt 1 by means of two rivets 24 and 25 and a fishplate 26. Thus, during rotation, the conveyor belt 1 is pulled by the drive members 22. The drive members 22 are arranged below the upper run 1 a of the conveyor belt 1, so that material being conveyed along the curve can project beyond the outside of the curve of the conveyor belt 1.

According to this invention and in a conveyor belt curve of this kind, at least one of the two rows 75 6 and 7 of rollers is designed to be swung from the surface of the upper run 1 a of the conveyor belt 1. Thus the rows of rollers can easily be removed and the conveyor belt easily withdrawn.

Furthermore, the rubbing plates or supports between the inner edge 5 and the outer edge 4 are so mounted as to form a slot. The conveyor belt, relieved of tension, can be readily removed upwardly through this slot.

In the first form of construction, illustrated in Figure 4, the row 6 of rollers is supported by the shaft 9 in a swivel head 41 comprising roller carriers 33 having a bore 9a for receiving the shaft 9 and having a screw-threaded bore 9b which is arranged radially in relation to the bore 9a and is receiving a set-screw for securing the shaft 9 relatively to the roller carrier which forms a direction-changing head 33 which, by means of screws 34, carries a spacer for a row 31 of cylindrical end rollers. The swivel head 41 also comprises head plates 35 each having a slot 36 for holding the shaft 9 together with the direction- changing head 33 and the spacer 32. The head plates 35 are rotatably mounted by means of a rotary bearing 38 on a fishplate 37 secured to the stand. Thus, the rows of end rollers and other rollers can be swung upwards over the upper run 1 a of the belt. The conveyor belt 1, relieved of tension in this way, then permits the entire direction-changing head 33, together with the row 6 of rollers, the spacer 32 and the row 31 of end rollers to be removed from the slot 36 in the headplate 35.

For the purpose of repeatedly setting the same belt tension, an adjustable stop comprising a screw bolt 40 and a check nut 44 is provided, and for setting the end position of the row 31 of end rollers, a set screw 39 with a check nut 42 is present.

The swivel head 41' is illustrated in broken 115 lines swung out from the stand 30 of the conveyor installation. In the working position of the swivel head 41, shown in solid lines, it will be clearly seen that the axis of rotation 38 is disposed closer to the upper run 1 a than the shaft 9 in the direction-changing head 33, from where a force vector, being a resultant of all the forces at a point between the screw bolt 40 and the lever arm 35a of the head plate 35, extends in the horizontal direction, so that a tilting effect is achieved so as to secure the swivel head 41, particularly in the working position.

Figure 5 is a plan view of a conveyor belt curve similar to that of Figure 1, and Figure 6 is a sectional view similar to that of Figure 2. The only 130 difference is that the drive members 22 are arranged on the outside of the conveyor belt 1, and the guide and drive part of the belt is protected by a cover 61, 62, firmly attached to the stand. Parts similar to those in Figures 1 and 2 have been indicated by the same reference numerals as those used in Figures 1 and 2. These parts do not therefore need to be described again in detail.

The two guide rails 13 and 14 as well as the outer frame 50 of the carrier structure with the annular member 12 are secured to the annular member 13' attached to a frame 49. An inner frame 51 is secured to the framework element 49 on the inside of the curve. Retaining elements 52-55 for backing rings 56 and 57 are secured to the inner frame 51 as well as to the outer frame 50. A slot 58, which extends along the entire length of the conveyor belt curve, is formed between the two backing rings 56 and 57. Rubbing plates 59 and 60 are secured on the one hand to the outer frame 50 and the outer backing ring 56 and, on the other, to the inner backing ring 57 and the inner frame 51, so that the slot 58 extends to the upper run 1 a of the belt.

However, segmental rubbing plates could be arranged over the entire width of the belt, which plates could be removed in the direction of the periphery of the curve after the direction-changing heads have been relieved of tension and the cover 61, 62 has been removed. Such an arrangement would be particularly suitable in the conveying of goods of medium weight.

For conveying heavy goods and as shown in Figures 7 and 8, support rollers 75 are distributed over the length of the conveyor belt curve and between the outer frame 70 and the outer backing ring 7 1. The ends 74 of the shafts of these support rollers 75 are mounted in the channels 72 and 73.

These rollers can therefore be lifted out of their holders after removal of the conveyor belt 1 and can be cleaned or replaced. Trapezoidal rubbing plates 76 for also supporting the upper run 1 a of the belt in the zone of the slot can be arranged between the inner frame 51 and the outer frame 70. These rubbing plates, too, are not attached to the stand and they can be lifted and removed just as easily as the support rollers 75.

Figure 9 illustrates an arrangement of the framework member 49 and the support for a conveyor belt for handling wet material (the conveyor belt itself is not shown). The outer frame 50 and the inner frame 51 each comprise equidistantly spaced holders 80. The support elements take the form of T-section beams 81, the upright limbs 82 of which are inserted in recesses 83 in the holders 80 so that the outer faces of the cross bars of the T-section carriers 81 together form a surface for the conveyor belt. As can be seen from Figure 9, the T-section beams 81 can be lifted out after the conveyor belt has been slackened, so that the entire space between the outer and inner frames is free from impeding elements. Thus, in this case too, the conveyor belt can be directly lifted out without any complicated 3 GB 2 126 973 A 3 dismantling of parts of the conveyor system.

For the purpose of inserting the conveyor belt, the T-section beams 81 are fitted in the holders 80 between the upper run 1 a and the lower run 1 b 40 of the belt. Then the roller carriers 33 with the rows 6 and 7 of rollers are inserted into the head plates 35 and are swung downwardly. After the drive members 22 have been fitted, the conveyor belt curve is ready for operation.

Claims

1. A conveyor belt curve comprising an endless conveyor belt which is mounted between two rows of rollers supported on shafts which are secured on an outer frame and an inner frame and form an angle at least in one projection, resilient drive members securing the conveyor belt at its convex longer face to a conveyor chain, said conveyor chain being guided in guide rails defining the curvature, wherein the shaft of at least one of the two rows of rollers is secured in a directionchanging head which is mounted to be swung out from the face of the upper run of the conveyor belt, and means are provided between the outer frame and the inner frame forming at least one slot for the introduction and removal of the conveyor belt.

2. A conveyor belt curve according to Cfaim 1, wherein the directionchanging head is a swivel head which is rotatably mounted on a swivel shaft firmly connected to the stand of the machine.

3. A conveyor belt curve according to Claim 2, wherein the swivel shaft is arranged above a plane containing the resultant force vector occurring in consequence of the deflection of the conveyor belt arou - rid the direction-changing head.

4. A conveyor belt curve according to Claim 3, including setting means for establishing the tension in the conveyor belt and for immobilizing the swivel head in at least the working position.

5. A conveyor belt curve according to any one of Claims 1 to 4, including removably mounted support strips to support the upper run of the conveyor belt.

6. A conveyor belt curve according to Claim 5, wherein the support strips are formed by the cross members of T-section bars the uprights of which are inserted in supports secured to the frames.

7. A conveyor belt curve according to any one - of Claims 1 to 4, wherein for forming a support for the upper run of the conveyor belt, rubbing plates are provided on a backing means attached to the stand of the machine and present on the inside of the curvature, and on a backing means which is likewise attached to said stand and is located on the outside of the curvature, the latter backing means forming a slot with the said backing means at the inside of the curvature.

8. A conveyor belt curve according to any one of Claims 1 to 4, wherein as support means for the upper run of the conveyor belt, rotatable rollers are disposea outside the curvature, and support means are attached to the stand to form a gap leading to such rollers.

9. A conveyor belt curve according to Claim 8, wherein the rollers are arranged at least approximately at right angles to the guide rails for the conveyor chain, and the gap between the rollers on the one hand and between the rollers and the support means on the other hand are covered by removable rubbing plates.

10. A conveyor belt curve substantially as -hereinbefore described with reference to the accompanying drawings.

Printed for Her Majesty's Stationery Office by the Courier Press, Leamington Spa, 1984. Published by the Patent Office, 25 Southampton Buildings, London, WC2A lAY, from which copies may be obtained.